The stable Tomdroid, an application compatible with Tomboy Notes that you can use to sync notes between your desktop computer and Android device, works in read-only mode for now so you can only read the notes created on your computer, but you can't edit them or create new notes.

But there's some good news. Tomdroid 0.7 beta was released recently, adding support for editing and creating new notes along with other new features. The new beta version isn't available on the Android market (Google Play), but you can download the apk from Launchpad.

Tomdroid 0.7 beta features:

basic tablet support

two way sync along with the ability to create, edit and delete notes

rich text editor

automatic renaming of notes with duplicate title

automatic note saving on pause

ability to revert changes

note conflict resolution screen when notes are of different date and both older or newer than last sync date

automatic authentication - if you use Ubuntu One, pressing "Sync" on first launch is enough to authenticate and sync

updating progress bar with information on current task, number of notes